Bug: .env values true/false misinterpreted

[nerdyjan]

Environment variables only ever carry strings. Left as-is, an override such as GRAV_CONFIG__system__cache__enabled=false lands in config as the string "false" - and PHP's (bool) cast (used throughout core, e.g. Cache::init()) treats any non-empty, non-"0" string as true, silently doing the opposite of what was asked. Coerce the two boolean literals; every other value (numbers, arbitrary strings) is left untouched, matching prior behavior.

InitializeProcessor.php. Line 235

                if (is_string($value)) {
                    if (strcasecmp($value, 'true') === 0) {
                        $value = true;
                    } elseif (strcasecmp($value, 'false') === 0) {
                        $value = false;
                    }
                }

[AdilAzhariOmsan]

I'd like to take this one. Planning the minimal fix suggested here: coerce the true/false string literals to bool in the GRAV_CONFIG__* override loop in InitializeProcessor::initializeConfig() (case-insensitive), leaving numbers and every other string untouched. Will add a unit test and open the PR against develop.

[rhukster]

Thanks @nerdyjan, confirmed and fixed — @AdilAzhariOmsan's PR is going in.

Your diagnosis was exactly right, including the pointer at Cache::init(). Worth adding one bit of history: if you were using the DotEnv plugin on 1.7, it did convert these for you, but through its own .gravenv file rather than through GRAV_CONFIG__. That prefix has never converted anything, in 1.7 or 2.0. So when Grav 2.0 started reading .env natively, this is the piece that didn't come across.

The docs are getting a note about it as well, since the example there uses =true, which works by accident.